Grab-bucket.



No. 776,854. PATENTED DEC. 6, 1904. J. B. LADD & D. BAKER.

GRAB BUCKET. APPLIOATION FILED APR. 23, 1904. no MODEL. 2 SHEETS-43313111 1.

A TTOHNH.

No. 776,854; PATENTED DEC. 6, 1904'.

J. B LADD & D. BAKER.

GRAB BUCKET.

APPLICATION FILED APR. 23, 1904.

N0 MODEL. 2 SHEETS-SHEET 2.

WITIlE-S'SES: INVENTORS 776M 1', v I 2 m W l B7 My @a/E'd max- A TTOIHIEY.

UNITED STATES Patented December 6, 1904.

PATENT OFFICE.

JAMES B. LADD, OF WAYNE, PENNSYLVANIA, AND DAVID BAKER, OF NEWTON, MASSACHUSETTS.

GRAH-BUCKET.

SPECIFICATION forming part of Letters Patent No. 776,854z, dated December 6, 1904.

Application filed April 23, 1904. Serial No. 204,505. (No model.)

To all whom it may concern:

Be it known that we, JAMES B. LADI), residing at Wayne, Delaware county, State of Penn sylvania, and DAVID BAKER, residing at Newton, Middlesex county,l\ iassachusetts, citizens of the United States, have invented a new and useful Grab-Bucket, of which the following is a specification.

Our invention relates to improvements in grab-buckets, our object being to afford improved means for supporting and operating the relatively movable elements of said bucket and to maintain said elements in any desired relative position, our improvements being especially directed toward simplicity in construction and efficiency in operation, both with respect to promptness of action and the economy of force exerted.

Our improvement comprises a two or more element bucket, preferably of the clam-shell type, and crank-operated means for causing the opening and closing of said elements, the motive power for said opening and closing operation being preferably supplied by a local motor mounted on the supporting mechanism of our device.

Our improvement comprises means whereby the bucket elements are caused to open and close in quick succession a required number of times by the rotation. of a crank-shaft.

Our improved means provides that the greatest power on the bucket elements is exerted at the beginning and at the completion of the closing movement, at the times when the work is heaviest upon the motor.

Our improvement also comprises means whereby the bucket elements may be securely locked in the open or closed position by bringing the crank into the dead-center position.

A special feature of simplicity and strength in our improved means consists in suspending all the parts on a common shaft, both the operating and the operated parts.

Our invention comprises other improvements in details.

We accomplish our object by the mechanism illustrated in the accompanying drawings, in which same view-point as that of Fig. 2, the bucket elements being in the open position.

Similar numerals refer to similar parts throughout the several views.

The bucket elements 1 and 2 are supported by arms or levers 4 and 5, the arms 4t being [ixcd at their lower extensions to the bucket elements and pivotally secured at their other extensions to the crossbar 6. The arms 5 are pivotally secured at one extremity to the bucket elements at 7 and at their other ex tremities are loosely mounted on the shaft 8, the shaft 8 being ioosely journaled in the blocks 3, which are secured in loops of the supporting-cables 17. Upon this shaft 8 is also loosely journaled the motor 9, being secured by the cross-bar 10 in a relatively fixed position with one pair of supporting-arms 5. The pinion 11 of motor 9 is adapted to mesh with gear-wheel 12, rotatably rigid with shaft 8. Upon the outer extremities of shaft 8-are provided the cranks 13, to which are secured at 15 the connecting-rods 141-.

It will be seen by an inspection of the drawings that when the cranks 13 are in the upwardly-extending position, as shown in Figs. 1 and 2, the bucket elements are held together or in the closed position. WVhen the crank members 13 are in the downwardly-extending position, as shown in Fig. 3, the bucket elements are held in the open position in their maximum extent of separation. The simple rotation of crank-shaft 8 and cranks 13 will cause a reciprocative movement of said bucket elements to and away from each other. It

will be obvious that the direction of rotation of said cranks is immaterial, and they are therefore adapted to be operated by a reversible motor. An especial advantage of the feature is that the bucket elements can be instantly reversed in direction of movement age.

from any point at which their movement has been brought to rest. When the cranks 13 are in the upwardly-extending vertical position, as shown in Figs. 1 and 2, they are in alinement with the connecting-rods 14. The axis of rotation of said cranks 13 is also in alinement and positioned between the connecting-points 6 and 15 of the connecting-rod 14. This may be said to be a dead-center position, in which the bucket elements are securely locked together ready for the elevation of the load. Similarly, in the position shown in Fig. 3 the cranks 13 are again in the deadcenter position and the buckets are securely locked open ready to be lowered to receive or secure a load. By this construction also it will be seen that as the bucket elements approach the closed position and as the cranks 13 approach the upwardly-extending vertical position the power exerted by the cranks is relatively increasedthat is, as the angle between the line connecting the two axial points of the crank members 13 and the line of the connecting-points of rod 141 becomes less the leverage increases, which results in an increase of power exerted on the connecting-rod 1 1 until said crank assumes the upwardly-vertical position. A similar condition exists at the beginning of the closing movement from the position shown in Fig. 3. The power exerted by the cranks 13 is again greater at the commencement of said movement. This is of especial advantage, since said crank movement gives the motor the greatest power at the beginning and at the end of the closing move- -ment of the bucket when the work is heaviest upon the motor.

The facility with which a number of reciprocating opening and closing movements of the bucket elements may be caused by the simple rotation of shaft 8 results in an extremely efiicient bucket, because said elements are enabled to work their way by this reciprocative movement into the materials to be taken up until a full load is obtained. When the reciprocating operation is stopped with the cranks 13 in the upwardly-vertical position,the bucket, with its load, is securely locked in the closed position until the motor is again operated.

By the construction shown an extremely powerful operating mechanism may be provided. The motor-operated pinion may be small in diameter and the crank-operatinggear may be comparatively large in diameter, so as to afford any required amount of lever- A further advantage of this construcused in the art.

mechanism the operation of the device may be readily controlled at any convenient point distant from the bucket. Another advantage of the use of an electric motor in this connection is that an automatic controller or circuitbreaker, such as is now well known in the electric art, may be connected in the circuits of said motor. By such means the circuit may be instantly opened or the motor cut out of circuit in the event of the bucket elements encountering an obstacle which would interfere with or prevent their proper operation.

In Fig. 1 we show the conducting-wires 18 to the motor as forming the cores of the supporting-cables, while in Fig. 3 we show one of said conducting-wires 18 leading to the motor independently of said cables.

What we claim is- 1. The combination of cooperating reciprocative bucket elements and means for causing their reciprocation, comprising a crank and a connecting-rod operating between said crank and a bucket element, so arranged that the operative parts shall assume the dead-center position when the bucket elements are together.

2. In combination with a motor-operated grab-bucket, a supporting-cable therefor, and

an electric conductor to the motor included in the cable structure.

3. The combination of cooperating reciprocative bucket elements and means for causing their reciprocation comprising a motor-driven rotating crank and a connecting-rod operating between said crank and a bucket element, so arranged that the operative parts shall assume the dead-center position when the bucket elements are together.

4. The combination of cooperating bucket elements, motor-driven crank-operated means for causing the reciprocation of said elements, and dead-center means for locking the elements closed.

5. The combination of cooperating bucket elements, motor-driven crank-operated means for causing the reciprocation of said elements and dead-center means for locking the elements opened.

6. The combination of cooperating bucket elements, motor-driven crank-operated means for causing the reciprocation of said elements, and dead-center means for locking the elements opened and closed.

7. The combination of, cooperating bucket elements, crank-operated means for causing the reciprocation of said elements, a motor for actuating said crank-operated means and a crank shaft supporting said elements and means.

8. The combination of cooperating bucket elements, crank-operated means for causing the reciprocation of said elements, having a dead-center position when the elements are closed, a motor for actuating said-crank-operated means and a crank-shaft supporting the bucket elements, the motor and the motor-opconductor to said motor forming a core to said cable.

JAMES B. LADD. DAVID BAKER.

Witnesses EDWARD HARSHAW, MAE HOFMANN. 

